Yes, and his movement is what spawned the Jesus movement.
Many forget Jesus took off where John stopped. It was probably not just Jesus either, John seemed to have a LARGE following.
My own personal opinion is that the story of Jesus is an amalgam of the stories of several prophets in the John tradition, with mythology added to keep it alive.
John wandered around in the wilderness, wearing as little as possible, and surviving off the land, and he preached a rebirth through water baptism (analogous to the birth water?)
While I am not sure about the historical existance of Jesus, the combination of the way John acted and some of the ideas expressed through the gospels and credited to Jesus makes me think if anyone had contact with Buddahistic philosophies it was probably John.
Maybe someone with more historical knowledge of John and his cult could expand on this idea.